SI or DI of you could only have one

So my neighbor and I were talking about this over the weekend being we are outfitting his boat. If you could have only one in your fish finder. Would you rather have Downward Imaging or Side Imaging and why?

That would be si, and di never.

Why, because do doesn’t tell me anything 2d does and si tells me everything 2d doesn’t.

I’ve had si for probably close to 6 years and I bet I haven’t used my di more than 2 hours.

si saves time searching for structure
di only does a small beam like conventional sonar
si can reach out up to 240ft each side per pass

rod-man wrote:

si saves time searching for structure
di only does a small beam like conventional sonar
si can reach out up to 240ft each side per pass

This is what I’ve told him mostly. And seems to be the way he is going but I wanted another set of opinions to show him the same.

SI is nice while searching for fish or structure, but DI is valuable all of the time. I have DI running at all times to decipher size and quantity of fish which doesn’t always show up well with 2D. DI is also nice when fishing weeds.

I had SI 3 years ago and used the DI function mostly. I went 2 years with a DI only unit and had no complaints. This year I talked myself into adding an SI unit, but again I rarely use it.

Good to know. Thanks Fife!

There’s a lot of info on an si screen and even a 2d screen.

I think most people don’t completely understand either. Especially those who might prefer di over si.

Si simple can’t be beat as far as level of detail. I even use my si when anchored.

Only thing above si as far as fishing technology and level of detail goes is panoptix.

Spend hours understanding the technology and you’ll understand what you’re looking at and more importantly you’ll be able to use it to the best of its abilities

SI has more of a learning curve to understand truly what you are seeing specifically drop-offs, etc, but it is a far more useful tool than DI. I use them both in splitscreen mode with 2D. SI is the one that I pay the most attention to when scouting.

I would bet i spent at least 15 hours learning the SI technology in the first year i owned it. Reading Humminbird forums, BBC forums, talking to HBird representatives, absorbing all info possible.
I’ve spent thousands of hours applying what i’ve learned. I think i’ve read the technology cover to cover so to speak and have had many hours of operation to apply everything learned.

my simplist explanation to a newbie SI user is to imagine the SI duecer is a flashlight shining a thin beam 180 degrees. It lights up everything it sees and creates shadows for everything it doesn’t see. This special flashlight also lights up objects brighter the harder and closer the object is and shows dim when the object is soft or further away.
You can judge distance of an object. Height of an object. Width of an object. Composition of an object. Shape of an object. SI shows you bubbles from boats passing by. It shows you bug hatches, baitfish, spawning beds, gravel, sand, rocks, mud, mud/sand, etc.etc.etc. SI has the detail to show you temperature transitions in the water column – thermoclines. Pretty awesome stuff when you understand its capabilities.

Even 2d requires a several hours of studying for you to fully understand what is happening. There’s a lot of detail that goes unnoticed by most people.

When i have someone new to the technology who’s not necessarily new to a 2d depthfinder i put them side/side. I point things out on the SI and then show them how that shows up on the 2d. Most everything that shows up on SI shows up on 2d to some degree with the exception of anything outside the 2d cone; that’s where SI provides a larger footprint of coverage.

Anyway. Go SI and set aside some time to learn how to use it before you hop in the boat.
You MUST understand how your SI works in order to decifer a bottom hugging fish from a rock etc etc.

Anchor your boat and watch your SI screen. You get to watch fish swim by the boat. You can see which side they are on. You can literally cast right to them.

Troll close to a dock, then look at your SI to find fish under that dock. You might not be impressed with the image of a dock. It’s just a few vertical poles and a tire or two. It is important when first learning to go by objects that you know and then you can understand why it shows up the way it does on SI.

I fish often with a buddy who has not spent any time trying to understand the technology. He’s now on year 2 or 3 with his SI. When fishing with him he’s constantly pointing out something and intrepreting it WRONG. “No, that’s a rock on a ledge; which is why it has a longer shadow”; “No, that’s probably an anchor drag and since it is in shallow water than we are and 80′ out it looks like a ledge, but the SI doesn’t have the angle to see past the small ridge of that anchor drag”

It’s almost annoying how he hasn’t absorbed this information yet…But a constant reminder of how you must study to understand SI.

Lots of Great info here! I’m liking it.

Here’s where i did most of my learning; on the threads from YEARS ago. Probably the one location where you can find anything Hummimnird. Scan through a lot of past threads. There’s a lot of screencaptures with arrows pointing to what’s what that can be a great help. Spend several hours reading through the threads.

http://www.bbcboards.net/humminbird-image-interpretation/

That forum has been active for years and has representitives directly from HBird on there also. Any new technology (Onix, Helix, 360, networking, mounting, ETC) can be answered on there.

Thanks

Paul, while you guys are out buying that SI unit, get me one too please, thanks.

Seriously though, I dont have experience with either but covering ground looking for structure/fish I would want the side imaging.

I’m not footing the bill thankfully. I just get to spend his money hlping him set it up. LOL